gilliland



3 Sheets-Sheet 1.

(No Model.)

E. T. GILLILAND.

TELEPHONE GIRGUIT vAND APPARATUS..

No. 806,288. Patented Oct. '7, 1884.

N. PETERS, PhulLimngmmmr. whmmun. n. c.

(No Model.) 3 Sheets-Sheet 2.

- E. T. GILLILAND.

TELEPHONE CIRCUIT AND APPARATUS. Y No. 806,238. l Patented 00's. 7,1884. t E gig, 5. @Z7

l u 1.a( @j C?) @Fvg r migl LU f l y Juge/neraog? 75 I?? "l N. PETERS.Phummnagmphr. wnmngw". llc.

(No Model.) 3 Sheets-Sheet 3.

E. T. GILLILAND.

TELEPHONE CIRCUIT' AND APPARATUS.

No. 306,238. Patented Oct. '7, 188.4.

N. PETERS, Pmwmnngmph, waslwmmn. D, c.

UNITED Srnrns artnr Ormes,

.AMERCAN BELL TELEPHONE COMPANY, OF SAME PLACE.

TELEPHONE CIRCUIT AND APPARATUS.

SPECPICATION forming part of Letters Patent No. 306,238, dated October7, 1884.

Application filed April :21, 1884. (No model.)

To @ZZ whom it may concern:

Beit known that I, EZRA T. GrLLiLAND, oi' .Bostoin in the county ofSuffolk and State of Massachusetts, have invented certain Improvementsin Telephonic Circuits and Apparatus, of which the following is aspecification.

My invention relates to systems of electrical intercom munication, andis intended espe. cially for use in conjunction witharticulatingtelephones. The ordinary telephonie central office77 orexchange consists, as iswell known, of a central or exchangestation,which is connected with a number of sub-stations by. means oftelegraphic or telephonie lines ra-V diating therefrom, these latterbeing so organized and arranged that any two of the substatious may beplaced, at a moments notice, (usually through the instrumentality of aswitch-hearth) in direct telegraphic or-telephonic communicationrwitheach other by the act of an attendant or operator at the central orexchange station, who, upon being notified to do so, connects the twovlines leading to the respective sub-stations, so that they are enabledthereafter to communicate with one another directly. Suitable signalingappliances are of course provided at the said central station, wherebysignals may be received from and transmitted to sub-stations. Such anorganization has proved very serviceable in a large number of cities andtowns, and has gone into general use. Experience has, however,demonstrated that many small towns and villages throughout the countryare debarred from the use of such systems by reason of the expenseattaching thereto, for, inasmuch as the number of persons desiring toavail themselves of telephonie privileges and facilities insparsely-populated localities is necessarily small, it frequentlyhappens that a sufficient number of subscribers who are willing to pay arental'high enough to make a central-office system profitable cannot beobtained, for the expenses of office rental and manipulation aresubstantially as great in an exchange of forty subscribers as they wouldbein an exchange of one hundred. These considerations have induced me todevise a system of intercommunication for such towns as are unable tosustain the expense of a regular exchange in which the centralstation,with all its paraphernalia of switching and signaling apparatus,together with the operators or manipulators thereof, are tot-allydispensed with.

The object of my invention is, then, the establishment of an economicalyet efficient system whereby a number of telephone-stations upondifferent main lines may freely signal and communicate with one another,dispensing altogether with the use of a central station or a centralapparatus, and without the introduction of complex or expensivemachinery or instrumentalities.

For the accomplishment of these purposes my invention consists, broadly,in a series of sub-stations, and a series of main lines extendingbetween and entering all of the said substations, a looping-in switchbeing provided at each station, whereby the subscriber may introduce hissignaling mechanism and telephones into any one ofthe main-linecircuits, and call and converse with the sub-stations normally connectedthereon.

It consists, also,in connecting the said apparatus at each stationnormally in any particular one of the said main lines, so that when theentire system is quiescenta certain number of stations-say live-arenormally connected in and with N o. l main line, live more with vNo. 2main line, live more with No. 3, and

so on. rlhus any station may call and com- Vmunicate with any otherstationv on the same line without a change .in its connections, and may,furthermore, connect with any station on any other line by transferringhis instrument-loop to the said line. Each sub-station therefore has itscalling and telephonie instruments normally connected in one of the saidmain lines, and is understood to be so connected by all stations, whileat the same time each station has the power of withdrawing itsinstruments 'from their normal location, and of transferring them to anyother of the entering main lines, so that the stations on those linesmay readily be called and communicated with.

In carrying out my invention I have devisedseveral ways of accomplishingthis transfer; and my invention further consists in apparatus wherebythe said transfer of the instruments from one line to another, as alsotheir IOO restoration, may be manually eil'ected, in apparatus wherebythe operationis made partly automatic, and in other apparatus wherebythe transfer may be et'tected either manually or automatically, whilethe restoration is completely and solely automatic.

In carrying out my invention, in order to eitcct the automaticrestoration of the apparatus from any main-line circuit in which it hasbeen placed to its normal line-wire, I have found it desirable to employa switch or circuit/changer which may be set by the opera tor prior tothe removal of the telephone from its support, so that thetelephone,whcn so removed, will be introduced into any desired line towhich it is set, and so that when tlie telephone is replaced in iissupport the nor mal condition ot' things is automatically rcstorcd, andthe station-instruments replaced in their normal circuit, or,with t-heexception ot' the signal-bell, withdrawn from all ot' the circuits. Sucha switch or circuit-changer is shown and described in patentissued .Tuly1S, 1882, to Theodore N. Vail, and numbered 261,186, and to that patentreference may be made. l have also :tfound it very convenient to employat cach station a short cable, in-- eluding all the necessary wires,whereby the several line-circuits may be led into and out ofthe saidstations. rihis extends, preferably, outward to the .nearest pole.

In the drawings by which my invention illustrated, and which constitutea part of this specification, Figure l is a diagram showing several mainlines extending between a numbcr of stations. Fi Zand 3 are respectivelyi'ront and side views of the terminal pole at each station, showing themethod of entering. Fig. 4 is a diagrammatic drawing oi" a stationapparatus adapted for manual operation. Fig. 5 is also a diagram ot' thestation-circuits and apparatus, arranged partly for automatic operation.Fig. 6 is a plan view of one form ot' telephone-holding switch which lincorporate in my station apparatus. Fig. 7 is an elevation of the same,showing also the station signaling zimiai'atiis and the severalcircuitloops. Fig. 8 is a detail ot' the circuit-chang ing device. Fig.t) shows another iorm ot' switch, worked by the telephoncsupport,together with the circuit arrangements. Figs. Il() and 1l are sideelevations ofthe switch shown in Fig. 9, illustrating the two positionsof said switch. Fig. 12 is a view of the entire switch andtelephone-holder incased in a singie box. Fig. i3 is a modified form ofFig. (i, showing the instrumental. loop carried out, and indicating thecomplete arrangement shown in Fig. 1 4. Fi li illustrates the mostcomplete circuit arrangement which i have devised, in which thestat-ion-instrumcnts are all maintained in one of the circuits when thetelephone is in its support; and Fig. l5 is a diagram of a similararrangement in which 5 the signaling-instruments are shown in one brauchcircuit and the telephones in another.

My invention contemplates a number o't' main-line wires, W, extending toand between any number ol" stations, A, and entering all ol' the said.stations. XVe may suppose, i'or example, a system ot twenty subscribers,in which ease four main lines might each extend to the twenty stations,entering them all. Each ot' the stations may, however, have itsinstruments, or a part thcreol', normally connected with some detiniteone ot' the wires, while at the same time the said instruments. or oneor more ot' them, may be capable ot'being withdrawnfrom that specificline and be connected with any one ot` the other, lilies. in the castIll have instanced there are tive stations normally connected with eachline, and it is obvious that it must be clearly understood by all thestations which line any specijtic station is normally coimccted with, tothe end that it' a station connected with one ot' the lines de; sirescommunication with a station on another line it may at once connect itsinstruments in the loop belonging to suchv line. rlhe wires V aresupported between the stations A, A, AL', A, and A1 on poles, in theusual. manner, and inasmuch as it is evidently inceiwenient to bring allthe wires loose into each station, l supply the stationpole with asuitable cover or cap, C, in which the several lines 1 terminate atbinding-screws s. A compound conductor-cable, K. then extends i'romthese bind ing-screws down the pole, as shown in Figs. i and 3, and intothe stations.

The station apparatus comprises, as usual, a signal-bell for indicatingincoming signals, a generator or equivalent device For scudi n our goingsignals, anda telephone or telephones. (Atransinitting-telcphoue is notessential, but is preferably employed.)-

ihe principle oi' my invention clearly shown in Fig. et., whichrepresents a diagram ot'the station circuits and. appiratus adaptedexclusively for manual operation. At each station the several lines j',after issuing i'rom. the cable K, may be terminated as shown. in thefigure, which is assumed to represent one of the stations in which theapparatus is normally connected with main line No. 1, Il( is theentering cable, which maybe composed ot' any number of conductiiigwiies,f. present instance I show four loops, each constituting the in and outwire ot' a single main line. The several lines are numbered l, 2, .5.and 4. In the special station under consideri ation a call-bell, i), ispermanentlyincluded inloop l, and this station is said to be connectedin lino-circuit No. il.. iach oli'the other loops, 2, 3, and Li,terminate in thisI station and in thc other stations ou No. ll4 wire inspringjacks J, into which the signaling and telcphone apparatus ol' thestation-:ma y be looped by means ofthe i1istriuncntalities which l, amnow about to describe. A casing, E, ineloscs a magnetogenerator, whichis operated by the crank c, and a levei'switeh, 7l, i'or transi'crringthe tlu'ouglreireuittrom the generator to the telephones, and also, whendesired, for closing the circuit oi the transmittor-battery ITS in theseparated by a sheet of some suitable non-cond. The magnetotelephone T,when not in l use, is hung on the hook it, and, by means of the cord c',is so disposed, in a manner well understood, as to be adapted forinclusion in the circuit of the wedge IV and conducting-cord e whenremoved from the said hook. rIhe transmitter T is not essential to theworking of the apparatus, but is preferably employed as facilitatingconversation. It also is, when employed, included in thetelephone-circuit and brought into action by the removal of themagneto-telephone from its support. rIhe entire apparatus is in the loope', which, by means of the wedge, (which is one ot' an ordinarycharacter, consist-ing of two metallic surfaces ducten) may be includedin any of the lines entering the station by means of their severalspring-jacks J. W'hen the station is not in communication with any otherstation, the wedge NV is preferably left in the spring-jack J ot'circuit No. l, so that the station-instruments form apart ot' the saidcircuit; or it may, at the option of the subscriber, be leftdisconnected from all of the lines, leaving the signalbell only incircuit. It', however, the subscriber should inadvertently leave thewedge in any of the spring-jacks belonging to the other line-circuits,the only adverse result is in the additional resistance thus thrown intothat circuit, since the alarm-bell is still inlinecircuit No. l, wherebycalls may be duly received; yet in sonic cases it may be found desirableto include the signal-bell in the loop controlled by the wedge \V, and Imay so connect it, if I prefer, without departing from the spirit ot' myinvention. Stations on lines 2, 25, and Aidesiring to communicate withstations online No. 1, will insert the wedge NV into the jacks J, whichthere represent No. 1, and call the required signal of the station theydesire. In like manner stations on No.1, desiring to communicate withstations on Nos. 2, 3, or 4, will insert the wedge \V into the jack J ofsuch line-circuit and call and converse.

I will now proceed to describe the apparatus by which I effect a certainamount of automatic operation in these devices.

Fig. 5 represents the complete apparatus, and Figs. 6, 7, and 8 enlargeddetails of one l'orm ol`- the automatic and circuit-changing apparatus.The chief distinction of the organization shown in Fig, 5 from that inFig. 4 is that the spring-jacks J ot' the ditl'erent lines are allincorporated with and inclosed in the mechanism in the case E, and thatby turning the handle n, which projects from the front ot' the case, tothe figure l, 2, 3, or et, representing the desired line, the subscriberor operator is enabled to determine before he removes his telephone fromits support which line he will be connected with. The several lines.asin the preceding view, enter the station Aby the cable K. They aredivided and pass to the generator and switch-case E, No. l first passingare connected with one another on a branch of the operative loop, asbefore, the shunted generator being in another branch of the saine loop.

te'erring to Figs. 6, 7, and S, it will be seen that the severalline-loops terminate i n as many spring-jaws J to J each of which isindicated on the front oi' the case by an index-number, and that thesignal-bell D may be placed in the circuit ot' that one of the saidline-loops to which it belongs-in the present illustration, No. l. Fig.S shows a side view of one of the said jaws J and o3t` the wedge XV',adapted for insertion therein. rlhe telephone-support 7L, which ispivoted at fu, and which is adapted to operate as the ci rcuit-changer,is formed of two sides, 0 and o, insulated from one another by aninsulating-partition, o', oan-y suitablcnonconducting material. Oneterminal, 5, ofthe generator and telephone-box, by means of acontact-spring. fr. rests on a collar of the pivot @awhile the otherterminal, (i, of the said loop, similarly rests by the spring o upon thecollar of the complementary pivot u, thus constituting a telephone orgenerator loop adapted to be completed by being included in any one ot'the entering` line-wires.

rIlhe details of the said telephone-loop may be understood by referenceto Fig. 7, in which it is fully delineated. The contact-springs s and siare merely terminals ol" the transmitterbattery circuit of which thewires and c are a part. The said circuit is at this point, for obviousreasons, normally open, and when the telephone T is removed from itssupport the lever iiies upward under the influence of the spring S orits equivalent, and brings one of the sides o and o into contact withthe two i'lat springs s and s2, uniting them electrically and closingthe circuit. A lever, L, provided with handle, a, pivoted at l), andcapable of swinging in a horizontal plane, has a slot, r, cut throughit, iu which works the head it" of the wedge W, which, as in Fig. 4,consists of two metal surfaces, m and m', separated by a non -conductingpartition, t'. The entire wedge, although controlled by the lever L, issupported on the telephone-switch lever Il, which passes through thewedge bythe square hole o2, the said wedge being capable of slidingfreely along the said telephone-lever when moved by itscontrolling-lever L. The metal surface m ot' the wedge is in electricalconnection with the side 0, and the surface mis similarly incontact withthe other side, o, of the telephone-switch lever. An index, as, issliown on the front ot' the box E, and the handle ot' the leveigL may beturned opposite to the tigure representing the desired line. rIhe wholeis arranged so that by turning the said lever until the handle thereofis opposite the required number the station-instruments, or such partot' them as may be transferable, may be introduced into the circuit ofthe line-wire with which the station to be communicated by one of itsloop-wires to the station signalwith is normally connected, whereupon,if the bell. The telephone receiver and transmitter l telephone T isremoved from its support, the

IOO

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spring S draws down the rear end el' the pi\'- oted switch-lever,forcing the wedge YV between the spring-jaw J ot" the desired linewire.rlhe required stations may then 'besig naled by turning the crank c,aller which conversation may be carried on. In this plan it will be seenthat the calling station must remove his telephone from the supportbefore he can call a second station. Conversation may already be passingover the line, and would be broken in upon were the subscriber to callwithout iirst listening; but the fact that the subscriber must iii-stremove his telephone will tend to remind him invariably to listen andascertain that the liuc is not in use betere he sends the call-signal,while the additional resistance of a single telephone and transmittermakes no practical ditlerencein thewm-king of the line.

Figs. t) to 12 exemplify a modification ot' the above combination. F 'l0and ll are sectional elevations oll the switch or cireuitehangcr shownin the said moditcation. It consists o1" aseries ol'spindles--one foreach linerircuit-which, when in theirnorlnal position, maintain the loopof their respective lineeir cuits closed, but which,whenpushedin,introduce the station aplmratus into th e linecircuitol"theparticularspindle pushed. Anynuniber ol" such. spindle-switchesmay be employed, according to the number ot" the entering` lines. llhave shown tour. Each switch consists ot'a noirconducting base, N, onwhich a spindle, t, is capable ot` sliding longitudinally when pushedinward by the button (g, or when retracted automatically by itsretracting and conducting'springs uf-' The spindle carries anon-conducting block, zr", in which is lett a single conducting-plate,./r', crossing the said block, and two other conductingplates, mi,insulated from one'another, but each in elcctri cal connection with oneof the wires oi" the gen` erator and telephoneloop, as shown in thediagrannFig. 9. The plates are in electrical connection with the pointsnf, to which the springs un' are attached, and the circuit is from thesethrough the springs to the screw in, and from thence by the wires 5, (i,7. 8, 9, and l0 to and through the generator M, magneto-telephone T, andtransmitter T', the generator, however, being normally shunted by thewire t), which in practice is broken either manually or by the movementot' the crank c when the call is being sent. lhe wires and (i ot' thetelephone-loop are branched to each oi" the spindle-switches, where theyremain as open terminals until any special spindle is pushed in. Theseveral main-circuit loops entering7 as shown in Fig. t), are madenormally complete or continuous by their contactsprings q and q', whichrest upon the conducting-plates a. Then the spindle is pushed in, thesaid springs are brought each in contact with one ot' the plates r2,which, be ing permanently in circuit with the telephoneloop, constitutesthat loop virtually a part ot' the line-circuit. Any spindle so pushedin would, by the constant tension of thcsprings ln.12,withdraw itself assoon as the pressure was .removed from its button Q, it' means were notprovided for its retention. It will be observed that on each spindle isan upwardly-projecting stud, R, and that attached to the telephone-support lever is a lug, ar, projecting downward and inward. Se long as thetelephone rests on the yoke h the lug .fr/,which is attached Vto thepivot-rod V, is prevented from engaging the stud but it' the telephoneis irst removed and any ot' the spindles are then pushed in, the studRol` that spindle passes the end ol' the lug, andthen on the attemptedwithdrawal ot' the spindle engages therewith, the said lng being broughtinto its path by the retractil spring S, which is attached to 'theheel7L ol" the telephone-switch lever. The spindleis thus locked, and t-hctelephone-loop is brought into the circuit of the main linerepresentei'l by such spindle until the telephone is replaced, when thelug reeedes, freeing the spindle, which thereupon i'lies outward. Theaxis ol' the switch-lever is furnished with as many cams or lugs .r asthere are spindle-switehrs, and thus is enabled to control them all. Theline-loops 2, (5, and 4 are merely indicated in the drawings.

Fig. 12 is a representation of the spindleswitch arranged in a compactcase, Y, independent ot' the generator and telephones,

From the foregoing descriptioiil it will appear thatany stationoperatordesiring to communicate with any other sta-tion will first .remove histelephone, will then push in the spindie et' the line with which therequired station is connected, will listen to sec il'such line isalready in use,and then proceed. to call and converse with the requiredstation; and that when, on the conclusion ot' the conversation, hereplaces his magneto-telephone the spindle will automatieallybe freedand ily outward, thus disconnecting the telephones. The stationcall-bell is, as before shown, pernmnently con nccted in its owncircuit.

The plans which up to the present point in this spceitieation have beendescribed, while showing the signal-bell constantly in circuit with oneline, show no means of maintaining the signal-sending and telephonieapparatus in such line7 or of restoring t-he saine thereto after it hasbeen used in any other line. The plans shown in Figs. 13, 1i, and l5ali'ord such means. In these organizations the complete apparatus ismade to depend i'or .its external connection upon the condition ot' theconduct ing-sides 0 and o ot' the switch-lever, which practicallyconstitute the terminals ol' a nor4 mally-open telephone-loop which maybe eon nected with any circuit. In every respect thetelephone-supporting switch itseltdepicted by Figs. 18, l-i, and 'l5 isidentical with that shown in Fig. 6, and hereinbei'ore described. rllheloop leading from the sides o o byineans ofthe springs '0 and 'U' is,however, shown in detail. The switch has, moreover, an additionalattachment. The switch-leveris 'fitted with an extra I OO ITO

IISI

.same time totally disconnected.

double wedge, 20, by which its two sides o and o', when the telephone Tis in place, supported by the switch, are brought into connection withthe two jaws of an auxiliary spring-jack, 21, all of the jacks J beingat the This auxiliary jack 21 is in the circuit of the wire to which thestation is supposed to belong. In this case, therefore, it is in circuitwith the spring-jack of No. 1 circuit, and as the loop of the generatorM and telephone T is always connected with the two sides of theswitchbar, the. said loop is thus normally, by means of the extra wedge20 and jack 21, connected with circuit No. 1, virtually constituting apart of said circuit. The path of the circuit entering the station isthen by wire 1 into the signal-bell D; from thence to onespring of theauxiliary jack 21 to one side, m, of the wedge 20 to the side of theswitch-lever, to pivot-collar u, spring v, wire 5, generating appara-tusM, wire 8, telephone T, wire 6, spring o', collar a', switch-lever sideo to the other side, m', of the wedge 20, front side of the auxiliaryspring-jack 21 to one side of the spring-jack J, normally byspring-contact to the other side of the same jack, and then out to line.Then this plan is adopted, the subscriber may, if he so desire, signalby operating his generator without removing his telephone from itssupport.

Although I prefer the arrangement of contact-springs v shown in theiigures, in which they are in frictional contact with the pivotcollars uand a, because by so placing them there is very little mechanicalresistance offered against the free movement ot' the lever on -itspivots, there are many other Ways which will readily suggest themselvesto those skilled in the art.

In practice the same switch-lever which I employ for the purposehereinbefore described is also utilized, in a manner well understood, tomake any other necessary circuit changes, such as cutting out thesignaling-instruments and introducing the telephone. I do not, however,regard it as essential to recount such attachments circumstantially, asthey are not material to my invention. In Fig. 15 I have indicated thatsuch changes may be eiiected by placing the manual button-switch Sin theinstrument-loop circuit, and including the signaling-instruments in onebranch thereof, and the telephones in another. Normally, the

g switch Si is turned to the button s, and the line-circuit No. 1 isthus led through the signal-bell and generator cia wire 6, wire 11, bellI), wire 12, generator M, wire 13, button s, switch S5, and wire 5.'When the subscriber desires to listen or converse over the line, theswitch is turned to s, and the circuit is from wire (i to wire 11,telephone T, wire 7, transmitter T/, wire 15, and button s6.

To the end that my invention shall be thoroughly understood, I willdescribe the operations necessary ior a complete communication.

CTI

Suppose that No. 2 on line No. 1 desires to talk with No. 1+i on lineNo. 3. The subscriber at No. 2 will, it' the plan shown in Figs. 5, (i,7, 13, 14, and 15 be adopted, first turn the lever L till the button acomes opposite the iigline and restores the normal condition of thevcircuits.

It is obvious that a system such as I have described presents manyadvantages. A central office, with its expensive apparatus and necessaryoperators, is dispensed with. Each sub-station is known by all themembers of the system to be always on his own line-wire, and can besignaled there, and each sub-station, while in a line of comparativelylowresistance and in normal circuit with but iew other stations, iscapable of being readily put into connection with many other stations,each of which is always to be found on its own line. Each sub-station,moreover, caureadily ascertain whether any other station is or is notalready busy, and,`as he can communicate directly with any station, canalways understand the reason of delay in obtaining the desiredcorrespondent. Furthermore, each station, upon the conclusion of aconversation, is automatically restored to its original condition, andthe resistance of all lines is thus kept at a minimum.

I do not in this application claim any specia form of circuit-changingswitch, per se, as any desired i'orm may be employed, and as, moreover,I propose to iile a separate application. for Letters Patent for one ofthe forms I have herein shown-to wit, that illustrated in Figs. 9, 10,11, and 12.

I do not regard the establishment of a number of line-circuits, all oiwhich enter all the stations together, with a single station apparatusadapted to be included, at the pleasure of the operator, in either ofthe said lines, as being new, parte, as I believe such a system to bewell known in the ordinary practice of commercial telegraphy, an d I donot broadly claim such a system; but

' Vhat I do claim as oi' my own invention is- 1. A system of telephonieintcrcommunieation comprising a number of subscribers stations connecteddirectlytogether, without the intervention of a central office, by aseries of main lines entering each station, a call-bell at cach station,permanently connected with one main line, and a single telephonie andsignal- IOO IIO

ing apparatus at each station, normally ineluded in the circuit of oneof the said main lines, but adapted to be withdrawn therefrom andintroduced into any other of the said main lines,whercby a subscribernormally connected wit-h any one ofthe lines may connect himself withany other of the said lines and communicate with subscribers normallyconnected therewith.

cation, a series ot' subscribers sta-tions connected directly together,without the intervention of a central ot'liee, by a series ot' mainlines entering each. station, each station being appropriated to aparticular line, so that a given number ot'stations are normallyconnected with eachiine, a cal l-bcll at each stati on,pe'r manentlyconnected with the particular main line to which that station belongs,telephonie and signaling apparatus normally connected with that line,and means, substantially as indicated, for witlnlrawing said telephonieand signaling apparatus it'rom the said main line, and Yfor including itin the circuit of any other main line, so thatcall and telephoniesignals maybe exchanged between it and the stations on the second line.

3. rlhe combination, substantially as hereinbefore described, ot` aseries of subscribers7 stations, a series ol' main lines, each ot thesaid lines extending to all ot' t-he said stations, a telephonie andsignaling apparatus at each station,normally in circuitwith one of thesaid main lirios, on which incoming calls maybe received. andconversation carried on, switching devices whereby the said apparatusmay be included l'or outgoing calls and conrcrsation in any other ot'the said main lines, and means for the automatic restoration ot' thesaid apparatus to its normal line-circuit upon the conclusion ot' acommunication, substantially as described.

l. rlhc combination, substantially as hereinbei'ore described, ot' aseries otsubscribers7 stations, a series ot` main lines, all ot' whichextend to and loop into all the stations, a series ot spring-jacks orother loop-receiving devices-one l'or cach line at each station-atelephonie and signaling apliaratus at each station, the said apparatusconsisting ot a signal-bell i'or receiving callvsignals, a generatori'or sending alls, a telephone or telephones, and a switch-barconstituting a support i'or the receivingtelcphone, with switch ingdevices included, normally, in one ot' the said main lines, but adaptedto be withdrawn therefrom and included in anyone ot' the Vlinccircuitsby means ot' the springjacks theretor, means, controlled by thetelephone-helding switch-bar, i'or maint-ai ning the said apparatus inthe desired linecircuit during thc displacement ot' the telephone, andother means, actuated by the telephone-holding sup port when thetelephone is .replaced therein, Vfor automatically transferring theapparatus to its normal connection.

5. In a system ot' telephonie inter-communication in which a number oistations are directly connected together by a series ot' mari-n linesand at each station ther-cot', a series ol' spring-jacks or otherloop-receiving and circuit-closing devices, each jack or circuiteloseritsclt' constituting a station-loop ol' a ,separate main-line circuit, asignal-bell for 2. In a system ot' telephonieintcrcomnnnnreceivingincoming calls perlmuiently connected in the circuit et' one ot' thesaid main lines, an instrument-loop including in its cir cuit agencratori'or sending outgoing call-signals and a telephone or telephones, andadapted to be normally included in and l'orm a part ot' that maincircuit in which the sfr- -nal-bell is connected, but capable oit'.transference therefrom to any other et' the said main lines by means ot'the respective loop-rccciv ing devices, whereby the subscriber at anystation is enabled to signal and converse with any station on any ot'the lines, and at the same time may receive a call-signal upon his ownline, substantially as described.

(i. In a system ot' telephonie communicz'rtion comprising a number ot'main lines entering all the stations and terminating thereat inspr'ingjacks-one for each mai nline-the combination ot' the tcleplmnieand signaling apparatus in a loop at each stat-ion, and the wedgeforming the terminals ot' said loop, said wedge being carried by thetelcplione-sumierting` arm, and being adjustable thereon, to makecontact with the spring-jacks ot' any line-cir cuit, whereby onadjusting the said wedge and removing the telephone the said loop isautomatically included in the desired mainline circuit, and on restoringthe teleiljihone such connection is broken, substantially as described.

7. In a telephone system ot' the character described, thecoml'iinaiioin, at a station, ot

the springiacks-one ior each main line-the wedge forming the terminalsot' a loop, includ ing the telephone and signaling apl'iaratus, saidwedge being carried by and adjustable on the telephone-supporting arm,so as to mahc contact with one oi' the sl'ii'ixig-jacl s when thetelephone is removed, an auxiliary springjack permanently included inthe circuit ot' the particular main line to which the station helen gs,and a second wedge, also carried by the supporting-arm, and arranged tomake contact with said last-named spring-jack when the tele] honc isinplace,wherebythe removal ol" the telephone automatically includes thesaid loop in one oi' the main-line circuits, dcterminml by the positionot' the zzdjustable wedge, and its replacement automatically restoressaid loop to the particular-line to which the station belongs,substantially as deseribtnl. In testimony whereot'I have signed my nameto this speei'tcation, in 'the presence ot" two subscribing witnesses,this lst-th day ot'ilrjiril, 1881-.

lZ M T. Gl'lllyllnltll). lVitnesses:

D. E. Rien-tiens, (tno. lVi'Lras lrunon.

